Psychology and the Law Research Methods
Plan for Today Research methods Class experiment
Levels of Explanation Poem written on a piece of paper a)Ink marks on paper b)Chemical constituents of paper and ink c)A collection of letters in English language d)A collection of words in English language e)A work of art and meaning
Research Methodology 1. General biases -self serving bias -I knew it all along phenomena 2. Biases in assessing covariation -illusory correlation 3. Biases in inferring causation -the fundamental attributional error -The illusion of control
Correlational vs. Experimental Research Smoking is correlated with lung cancer High grades are correlated with successful careers Eating Frosted Flakes is correlated with lower cancer rates In Taiwan birth control use is correlated with number of household appliances
Correlational Research Establishes whether there is a relationship between two or more variables CANNOT INFER CAUSALITY 1.Directionality problem 2.Potential for a third variable (confound)
Experimental Research Considered the most powerful tool for determining causal relationships Random Assignment: ensures that every participant has an equal chance of being assigned to any of the conditions This minimizes the chance that a pre- existing difference between groups is the cause of the “experimental effect”
Trial and Error Try something, if it works try it again, if not discard If it works again, try it again. If it works often, use it often. Problems: Harder to understand the mechanisms behind why something works. Ignores research in related areas.
Example word generation task OFRE CMPA KLIN ETPS
Word Generation Task ABTI CKSA HROM ETPL
Research Demonstration Purpose of study? – the effects of anxiety on performance Eperimental hypothesis? - anxiety will decrease performance, those in anxiety condition will generate less words than those in the control condition
Research Demonstration Independent variable? -made to feel anxious or not Dependent variable? -number of words generated Manipulation check? -people in anxiety condition will score higher on questionnaire than control condition
Research Demonstration Random assignment Random sample Internal validity External (ecological) validity Reliablility
Legal Quiz If I were charged with negligent manslaughter in Toronto: What type of offense would it be? What court would I be remanded to? Where would I appeal my conviction?
Legal quiz Who writes the laws of the land? What are the Division of Powers? What are the two dimensions of evidence? When can an opinion be offered by a witness in court?